#include <iostream>

// 函数调用顺序未指定顺序
void foo(int a, int b) {
    std::cout << a << ", " << b << std::endl;
}

int get_num() {
    static int i = 0;
    return ++i;
}

int main(int argc, char const *argv[])
{
    foo(get_num(), get_num());
    
    return 0;
}
